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Merge pull request #663 from IrgendwerA8/more_popptr1_adaptations

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Adapted div & mod for popptr1.
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Oliver Schmidt 2018-05-26 13:01:27 +02:00 committed by GitHub
commit 95223be101
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8 changed files with 60 additions and 70 deletions
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16
libsrc/common/abs.s
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@ -1,16 +0,0 @@
;
; Ullrich von Bassewitz, 17.06.1998
;
; int abs (int x);
;
.export _abs
.import negax
_abs: cpx #$00 ; test hi byte
bpl L1
jmp negax ; Negate if negative
L1: rts

16
libsrc/runtime/div.s
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@ -5,18 +5,18 @@
;
; When negating values, we will ignore the possibility here, that one of the
; values if $8000, in which case the negate will fail.
; values is $8000, in which case the negate will fail.
.export tosdiva0, tosdivax
.import popsargs, udiv16, negax
.importzp sreg, tmp1, tmp2
.import popsargsudiv16, negax
.importzp ptr1, tmp1, tmp2
tosdiva0:
ldx #0
tosdivax:
jsr popsargs ; Get arguments from stack, adjust sign
jsr udiv16 ; Do the division
ldx sreg+1 ; Load high byte of result
jsr popsargsudiv16 ; Get arguments from stack, adjust sign
; and do the division
ldx ptr1+1 ; Load high byte of result
; Adjust the sign of the result. tmp1 contains the high byte of the left
; operand, tmp2 contains the high byte of the right operand.
@ -27,11 +27,11 @@ tosdivax:
; Result is negative
lda sreg ; Load low byte of result
lda ptr1 ; Load low byte of result
jmp negax ; Adjust the sign
; Result is positive
Pos: lda sreg
Pos: lda ptr1 ; Load low byte of result
rts

14
libsrc/runtime/mod.s
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@ -5,19 +5,19 @@
;
; When negating values, we will ignore the possibility here, that one of the
; values if $8000, in which case the negate will fail.
; values is $8000, in which case the negate will fail.
.export tosmoda0, tosmodax
.import popsargs, udiv16, negax
.importzp ptr1, tmp1
.import popsargsudiv16, negax
.importzp sreg, tmp1
tosmoda0:
ldx #0
tosmodax:
jsr popsargs ; Get arguments from stack, adjust sign
jsr udiv16 ; Do the division
lda ptr1 ; Load low byte of result
ldx ptr1+1 ; Load high byte of result
jsr popsargsudiv16 ; Get arguments from stack, adjust sign
; and do the division
lda sreg ; Load low byte of result
ldx sreg+1 ; Load high byte of result
; Adjust the sign of the result. tmp1 contains the high byte of the left
; operand, tmp2 contains the high byte of the right operand. The sign of

1
libsrc/runtime/mulax3.s
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@ -3,6 +3,7 @@
;
; CC65 runtime: Multiply the primary register by 3
;
; Don't touch the Y-register here, the optimizer relies on it!
.export mulax3
.importzp ptr1

7
libsrc/runtime/neg.s → libsrc/runtime/negabs.s
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@ -1,11 +1,16 @@
;
; Ullrich von Bassewitz, 05.08.1998
;
; int abs (int x);
; and
; CC65 runtime: negation on ints
;
.export negax
.export _abs
_abs: cpx #$00 ; Test hi byte
bpl L1 ; Don't touch if positive
negax: clc
eor #$FF
adc #1
@ -15,7 +20,7 @@ negax: clc
adc #0
tax
pla
rts
L1: rts

19
libsrc/runtime/shelp.s
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@ -1,17 +1,17 @@
;
; Ullrich von Bassewitz, 07.08.1998
;
; CC65 runtime: helper stuff for mod/div/mul with signed ints
; CC65 runtime: helper stuff for mod/div with signed ints
;
; When negating values, we will ignore the possibility here, that one of the
; values if $8000, in which case the negate will fail.
; values is $8000, in which case the negate will fail.
.export popsargs
.import negax, popax
.importzp sreg, tmp1, tmp2, ptr4
.export popsargsudiv16
.import negax, popax, udiv16
.importzp tmp1, tmp2, ptr1, ptr4
popsargs:
popsargsudiv16:
stx tmp2 ; Remember sign
cpx #0
bpl L1
@ -24,7 +24,6 @@ L1: sta ptr4
cpx #0
bpl L2
jsr negax
L2: sta sreg
stx sreg+1
rts
L2: sta ptr1
stx ptr1+1
jmp udiv16 ; Call the division

45
libsrc/runtime/udiv.s
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@ -3,9 +3,10 @@
;
; CC65 runtime: division for unsigned ints
;
; Don't use tmp1 here, the signed division tunnels data with it!
.export tosudiva0, tosudivax, udiv16
.import popsreg
.import popptr1
.importzp sreg, ptr1, ptr4
@ -14,50 +15,50 @@ tosudiva0:
tosudivax:
sta ptr4
stx ptr4+1 ; Save right operand
jsr popsreg ; Get left operand
jsr popptr1 ; Get left operand
; Do the division
jsr udiv16
; Result is in sreg, remainder in ptr1
; Result is in ptr1, remainder in sreg
lda sreg
ldx sreg+1
lda ptr1
ldx ptr1+1
rts
;---------------------------------------------------------------------------
; 16by16 division. Divide sreg by ptr4. Result is in sreg, remainder in ptr1
; 16by16 division. Divide ptr1 by ptr4. Result is in ptr1, remainder in sreg
; (see mult-div.s from "The Fridge").
; This is also the entry point for the signed division
udiv16: lda #0
sta ptr1+1
sta sreg+1
ldy #16
ldx ptr4+1
beq udiv16by8a
L0: asl sreg
rol sreg+1
rol a
L0: asl ptr1
rol ptr1+1
rol a
rol sreg+1
pha
tax
cmp ptr4
lda ptr1+1
lda sreg+1
sbc ptr4+1
bcc L1
sta ptr1+1
pla
sta sreg+1
txa
sbc ptr4
pha
inc sreg
tax
inc ptr1
L1: pla
L1: txa
dey
bne L0
sta ptr1
sta sreg
rts
@ -65,18 +66,18 @@ L1: pla
; 16by8 division
udiv16by8a:
@L0: asl sreg
rol sreg+1
@L0: asl ptr1
rol ptr1+1
rol a
bcs @L1
cmp ptr4
bcc @L2
@L1: sbc ptr4
inc sreg
inc ptr1
@L2: dey
bne @L0
sta ptr1
sta sreg
rts

12
libsrc/runtime/umod.s
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@ -5,24 +5,24 @@
;
.export tosumoda0, tosumodax
.import popsreg, udiv16
.importzp ptr1, ptr4
.import popptr1, udiv16
.importzp sreg, ptr4
tosumoda0:
ldx #0
tosumodax:
sta ptr4
stx ptr4+1 ; Save right operand
jsr popsreg ; Get right operand
jsr popptr1 ; Get right operand
; Do the division
jsr udiv16
; Result is in sreg, remainder in ptr1
; Result is in ptr1, remainder in sreg
lda ptr1
ldx ptr1+1
lda sreg
ldx sreg+1
rts